Corrosion behaviour of die-cast AZ91D magnesium alloys in sodium sulphate solutions with different pH values

The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate （Na 2 SO 4 ） solutions with different pH values. The corrosion rates, morphologies, and compositions of the corrosion products were studied by means of scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy （FTIR）, and X-ray diffractometry （XRD）. The results indicate that the order of corrosion rates in Na 2 SO 4 solutions with various pH values is pH 2pH 4pH 7pH 9pH 12. The corrosion rates in acidic solutions are higher than those in alkaline solutions, and the corrosion products are mainly magnesium hydroxide （Mg（OH） 2 ） and hydrated sulphate pickeringite （MgAl 2 （SO 4 ） 4 ·22H 2 O）. The results also indicate that the solution pH can influence the corrosion rate and morphology of corrosion products. Chloride ions and sulphate ions have different pitting initiation time.

Attenuation of dextran sodium sulphate induced colitis in matrix metalloproteinase-9 deficient mice

AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5% DSS in drinking water for 5 d followed by recovery up to 7 d. On d 5 and 12 after induction of colitis, gelatinases, MMP-2 and MMP-9, were measured in homogenates of colonic tissue by zymography and Western blot, whereas tissue inhibitor of metalloproteinases (TIMPs) were measured by reverse zymography. The gelatinolytic activity was also determined in supernatants of polymorphonuclear leukocytes (PMN) isolated from mice blood. Moreover, intestinal epithelial cells were stimulated with TNF-α to study whether these cells were able to produce MMPs. Finally, colonic mucosal lesions were measured by microscopic examination. RESULTS: On d 5 of colitis, the activity of MMP-9 was increased in homogenates of colonic tissues (0.24 ± 0.1 vs 21.3 ± 6.4, P < 0.05) and PMN from peripheral blood in wt (0.5 ± 0.1 vs 10.4 ± 0.7, P < 0.05), but not in MMP-9-deficient animals. The MMP-9 activity was also up-regulated by TNF-α in epithelial intestinal cells (2.5 ± 0.5 vs 14.7 ± 3.0, P < 0.05). Although colitis also led to increase of TIMP-1 activity, the MMP-9/TIMP-1 balance remained elevated. Finally, in the MMP-9-deficient colitic mice both the extent and severity of intestinal epithelialinjury were significantly attenuated when compared with wt mice. CONCLUSION: We conclude that DSS induced colitis is markedly attenuated in animals lacking MMP-9. This suggests that intestinal injury induced by DSS is modu-lated by MMP-9 and that inhibition of this gelatinase may reduce inflammation.

Selective debenzylation of benzyl esters by silica-supported sodium hydrogen sulphate

A new debenzylation of benzyl esters by silica-supported sodium hydrogen sulfate is described. The debenzylation could be achieved selectively and efficiently in good to excellent yields without affecting sensitive functional groups such as nitro, unsaturated bonds, and ethyl ester.

Anti-tumor necrosis factor α therapy associates to type 17 helper T lymphocytes immunological shift and significant microbial changes in dextran sodium sulphate colitis

BACKGROUND Anti-tumor necrosis factor α(TNFα) represents the best therapeutic option to induce mucosal healing and clinical remission in patients with moderate-severe ulcerative colitis. On the other side gut microbiota plays a crucial role in pathogenesis of ulcerative colitis but few information exists on how microbiota changes following anti-TNFα therapy and on microbiota role in mucosal healing.AIM To elucidate whether gut microbiota and immune system changes appear following anti TNFα therapy during dextran sulfate sodium(DSS) colitis.METHODS Eighty C57 BL/6 mice were divided into four groups: "No DSS", "No DSS + antiTNFα", "DSS" and "DSS + anti-TNFα". "DSS" and "DSS + anti-TNFα" were treated for 5 d with 3% DSS. At day 3, mice whithin "No DSS+anti-TNFα" and"DSS+anti-TNFα" group received 5 mg/kg of an anti-TNFα agent. Forty mice were sacrificed at day 5, forty at day 12, after one week of recovery post DSS. The severity of colitis was assessed by a clinical score(Disease Activity Index), colon length and histology. Bacteria such as Bacteroides, Clostridiaceae, Enterococcaceae and Fecalibacterium prausnitzii(F. prausnitzii) were evaluated by quantitative PCR.Type 1 helper T lymphocytes(Th1), type 17 helper T lymphocytes(Th17) and CD4+ regulatory T lymphocytes(Treg) distributions in the mesenteric lymph node(MLN) were studied by flow cytometry.RESULTS Bacteria associated with a healthy state(i.e., such as Bacteroides, Clostridiaceae and F. prausnitzii) decreased during colitis and increased in course of anti-TNFαtreatment. Conversely, microorganisms belonging to Enterococcaceae genera,which are linked to inflammatory processes, showed an opposite trend.Furthermore, in colitic mice treated with anti-TNFα microbial changes were associated with an initial increase(day 5 of the colitis) in Treg cells and a consequent decrease(day 12 post DSS) in Th1 and Th17 frequency cells. Healthy mice treated with anti-TNFα showed the same histological, microbial and immune features of untreated colitic mice. "No DSS + anti-TNFα" group showed a lymphomononuclear infiltrate both at 5 th and 12 th d at hematoxylin and eosin staining, an increase of in Th1 and Th17 frequency at day 12, an increase of Enterococcaceae at day 5, a decrease of Bacteroides and Clostridiaceae at day 12.CONCLUSION Anti-TNFα treatment in experimental model of colitis improves disease activity but it is associated to an increase in Th17 pathway together with gut microbiota alteration.

Barium, Calcium and Sodium, Cyanide, Phosphate and Sulphate Contents of Groundwater in Some Ika Communities of Delta State, Nigeria

Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water for inhabitants of these communities without any form of treatment. 55 borehole water sites spread within these five sample sub-areas. The metal ions were analyzed using Solar Unicam flame Atomic Absorption Spectrophotometer. Sulphate, phosphate, and cyanide contents were determined by colorimetric method. Results indicate the presence of sodium, calcium, sulphate, and phosphate. However, barium and cyanide were below detection limit. Secondly, there was a relatively higher proportion of calcium and sulphate than sodium and phosphate in its aquifer. Thirdly, a mean ratio value of 0.018 and 0.158 was observed for the ratios of Na+/Ca2+ and ?respectively. Fourthly, sodium showed good correlation with all the other parameters. Finally, nearly all the studied parameters have concentrations below the maximum contaminant levels of the World Health Organization (WHO), invariably inferring that the water is wholesome with respect to the analytes. However, concern still remains from a health point of view on the sodium concentrations in many sample areas.

The Effect of Additives on Crystal Size of Sodium Sulphate

1 Introduction Anhydrous sodium,mainly produced in the United States,Canada,Japan,is indispensable commodities and raw materials in daily life and industry.In recent years,anhydrous sodium sulfate of general size was much oversupplied[1].However particles anhydrous sodium sulphate of large size is not adequate to the demand for its

Impact of Sulphate Counter Ion in the Migration of Sodium Ion through Soils

Laboratory advection-diffusion tests are performed on two regional soils-Brown Earth and Red Earth-in order to assess their capacity to control contaminant migration with synthetic contaminant solution of sodium sulphate with sodium concentration of 1000 mg/L. The test was designed to study the transport/attenuation behaviour of sodium in the presence of sulphate. Effective diffusion coefficient (De) that takes into consideration of attenuation processes is used. Cation exchange capacity is an important factor for the attenuation of cationic species. Monovalent sodium ion cannot usually replace other cations and the retention of sodium ion is very less. This is particularly true when chloride is anion is solution. However, sulphate is likely to play a role in the attenuation of sodium. Cation exchange capacity and type of exchangeable ions of soils are likely to play an important role. The effect of sulphate ions on the effective diffusion coefficient of sodium, in two different types of soils, of different cation exchange capacity has been studied. The effective diffusion coefficients of sodium ion for both the soils were calculated using Ogata Bank’s equation. It was shown that effective diffusion coefficient of sodium in the presence of sulphate is lower for Brown Earth than for Red Earth due to exchange of sodium with calcium ions from the exchangeable complex of clay. The soil with the higher cation exchange retained more sodium. Consequently, the breakthrough times and the number of pore volumes of sodium ion increase with the cation exchange capacity of soil.

Experimental and Quantum Chemical Studies of the Inhibition of Copper with Sodium Dodecyl Sulphate (SDS) in Acidic Medium

This work investigates the inhibitive properties of sodium dodecyl sulphate (SDS) on the corrosion of copper (Cu) in nitric acid using gasometric methods. The inhibition efficiency increases with time and concentration of SDS. The corrosion rate of copper decreases as concentration of SDS increases. Adsorption of the SDS on the surface obeyed the Langmuir adsorption isotherm. The high negative values of the kinetic parameter B suggest that the inhibitor’s effectiveness increases with temperature. The equilibrium constant and the free energy of adsorption of SDS to copper are negative and large. This observation implies that the adsorption mechanism maybe chemisorption. The quantum chemical calculation of copper dodecyl sulphate shows that the energy change in the HOMO-LUMO energy of the moiety is positive and small. This observation implies that the SDS is an efficient inhibitor. The high dipole moment obtained implies that corrosion inhibition of Cu is enhanced by adsorption of SDS and this observation correlates with the observed experimental inhibition efficiency.

Renal Toxicity of Nickel,Sodium Lauryl Sulphate and Their Combination after Dermal Application in Guinea Pigs

The guinea pigs were dermally exposed to nickel (Ni), sodium lauryl sulphate (SLS) and in their combination for 7 and 14 days. The exposure to Ni and SLS produced changes in enzymes and lipid peroxidation in kidney. The exposure to Ni or SLS depicted slight changes while combined exposure to Ni plus SLS exhibited more degenerative changes in kidney. The result of the study suggests that industrial workers and/or populations exposed simultaneously to Ni and SLS produces more damage to kidney.

姜黄素联合粪菌移植对DSS诱导的小鼠溃疡性结肠炎的改善作用

目的:探讨姜黄素联合粪菌移植对葡聚糖硫酸钠(DSS)诱导的小鼠溃疡性结肠炎(UC)的改善作用,并阐明其相关作用机制。方法:50只小鼠随机分为对照组、模型组、姜黄素组、粪菌移植组和联合组,除对照组小鼠自由饮用纯净水外,其余各组小鼠自由饮用含2%DSS的蒸馏水建立UC模型。姜黄素组小鼠灌胃给予60 mg·kg^(-1)姜黄素溶液0.4 mL,每日1次,连续10 d;粪菌移植组小鼠灌肠粪菌液0.2 mL,每日1次,持续10 d;联合组小鼠给予0.2 mL粪菌液灌肠后,给予60 mg·kg^(-1)姜黄素溶液0.4 mL灌胃。实验结束后,计算各组小鼠疾病活动指数(DAI)和结肠大体形态损伤指数(CDMI),HE染色观察各组小鼠结肠组织病理形态表现,酶联免疫吸附试验(ELISA)法检测各组小鼠结肠组织中白细胞介素(IL)-1β、肿瘤坏死因子α(TNF-α)、IL-4和IL-10水平,实时荧光定量PCR(RT-q PCR)法和Westernblotting法检测各组小鼠结肠组织中闭合蛋白(occludin)和闭锁小带蛋白1(ZO-1)m RNA及蛋白表达水平。结果:对照组小鼠结肠黏膜上皮结构完整且连续,腺体排列规则,无炎性细胞浸润和溃疡;模型组小鼠结肠黏膜上皮脱失,腺体排列紊乱,杯状细胞减少,黏膜和黏膜下层充血水肿,大量炎性细胞浸润,弥漫分布小溃疡;姜黄素组、粪菌移植组和联合组小鼠结肠黏膜上皮结构相对完整,炎性细胞浸润减少,黏膜和黏膜下层充血水肿减轻。与对照组比较,模型组小鼠DAI和CDMI升高(P<0.05),结肠组织中IL-1β和TNF-α水平升高(P<0.05),IL-4和IL-10水平降低(P<0.05),occludin和ZO-1 mRNA及蛋白表达水平降低(P<0.05);与模型组比较,姜黄素组、粪菌移植组和联合组小鼠DAI和CDMI降低(P<0.05),结肠组织中IL-1β和TNF-α水平降低(P<0.05),IL-4和IL-10水平升高(P<0.05),occludin和ZO-1mRNA及蛋白表达水平升高(P<0.05);与姜黄素组和粪菌移植组比较,联合组小鼠DAI和CDMI降低(P<0.05),结肠组织中IL-1β和TNF-α水平降低(P<0.05),IL-4和IL-10水平升高(P<0.05),occludin和ZO-1 mRNA及蛋白表达水平升高(P<0.05)。结论:姜黄素联合粪菌移植可改善UC小鼠结肠组织病理损伤,抑制炎症因子分泌,促进肠黏膜修复。

双碳背景下的废盐制碱工艺研究进展

综述了以卤盐和硫酸盐废盐为原料制碱的工艺路线及进展,对比分析不同废盐制碱工艺的现状和潜在问题。卤盐制碱工艺相对成熟,但仍然存在能耗较高和流程复杂等不足;利用硫酸盐制碱为废盐制碱提供了一条新思路,可与碳利用相结合,使生产过程更经济、更清洁,促进双碳目标的实现。总结并展望以硫酸钠和CO_(2)为原料制碱的发展前景。

甲泼尼龙琥珀酸钠联合硫酸镁治疗小儿喘息性支气管肺炎的临床疗效及对患者炎症指标的影响

目的探讨甲泼尼龙琥珀酸钠联合硫酸镁治疗小儿喘息性支气管肺炎的疗效对患者炎症指标的影响。方法选取2021年10月至2022年10月东台市人民医院收治的130例喘息性支气管肺炎患儿作为研究对象,按照随机数字表法分为常规组与观察组,每组65例。常规组给予甲泼尼龙琥珀酸钠治疗,观察组给予甲泼尼龙琥珀酸钠联合硫酸镁治疗,比较两组临床疗效、炎症指标[超敏C-反应蛋白(hypersensitive C-reactive protein,hs-CRP)、中性粒细胞百分比(percentage of neutrophils,NEUT%)、降钙素原(procalcitonin,PCT)]及不良反应发生情况。结果观察组治疗总有效率高于常规组,差异有统计学意义(P<0.05)。观察组咳嗽、气喘、肺啰音、气促症状消失时间及肺部炎症消失时间、住院时间均短于常规组,差异有统计学意义(P<0.05)。治疗后,两组hs-CRP、NEUT%及PCT均低于治疗前,且观察组低于常规组,差异有统计学意义(P<0.05)。两组不良反应发生率比较差异无统计学意义。结论甲泼尼龙琥珀酸钠联合硫酸镁治疗喘息性支气管肺炎患儿疗效显著,可缩短症状改善时间,改善炎症反应程度,值得临床推广应用。

兰炭基硬炭的微观结构调控及储钠性能

目前硬炭大规模生产主要受到制备工艺的限制。以兰炭为原料,经硫酸铵一步水热处理后进行1400℃高温炭化,制备兰炭基硬炭,采用X射线衍射(XRD)、拉曼光谱(Raman)、氮气吸附、扫描电镜(SEM)和透射电镜(TEM)等方法分析了兰炭基硬炭的微观结构及表面官能团等在硫酸铵水热处理与高温炭化过程中的演变规律,并通过恒流充放电、恒电流间歇滴定以及循环伏安测试等方法研究不同兰炭基硬炭用作钠离子电池负极材料的电化学性能,探索微观结构对负极材料电化学储钠性能的影响机制及兰炭基硬炭的电化学储钠机理。结果表明:通过调节硫酸铵水热处理温度可以精准调控兰炭基硬炭中各碳相的相对含量,从而达到提高其储钠性能的目的;当水热处理温度为260℃时,得到的样品(NLC-260)具有较高含量的伪石墨结构(32.4%)以及适量的无序结构(36.4%),表现出最佳的电化学性能,在20 mA/g的电流密度下可逆容量可达294.0 mAh/g,首次库伦效率高达83.0%,经1000次循环后容量保持率仍可达79.6%。

电石渣基碱激发剂对粉煤灰同步注浆材料影响研究

为促进工业固废电石渣资源化利用,减少相关污染与同步注浆成本问题。以电石渣作为粉煤灰基同步注浆材料主要碱激发剂,并针对电石渣和粉煤灰制备胶凝材料存在早期强度差的问题,添加硫酸钠与水玻璃制备了碱激发粉煤灰同步注浆材料。开展了以电石渣、硫酸钠和水玻璃为不同因素的正交试验,分析上述因素对浆液各试验参数影响敏感程度与规律,并进行多元线性回归分析预测与Gauss消去法求解优化制备模型,研究结果表明:随着电石渣掺量的提高,降低了浆液早期工作性能,但是可以提升结石体后期强度,水玻璃的掺入使试样早期性能得到提升,最终确定电石渣掺量为18.6%,硫酸钠掺量为2.8%,水玻璃掺量为0.6%的最优材料配比,28 d抗压强度可达10.39 MPa;XRD和SEM分析显示,同步注浆材料水化时随着养护龄期的增加产生大量水化产物,使注浆结石体具备较高后期抗压强度。

棕榈油酸对溃疡性结肠炎小鼠肠道菌群的作用

为研究不同存在形式的棕榈油酸(palmitoleic acid,POA)对溃疡性结肠炎(ulcerative colitis,UC)小鼠肠道菌群的调节作用,该文利用葡聚糖硫酸钠(dextran sulphate sodium salt,DSS)诱导构建溃疡性结肠炎小鼠模型,将60只雄性BALB/c小鼠随机分成正常对照组、模型组、柳氮磺吡啶治疗组、沙棘果油组、棕榈油酸组和大豆分离蛋白-棕榈油酸组(soy isolate protein-palmitoleic acid,SPI-POA),通过检测小鼠体质量、疾病活动指数(disease activity index,DAI)以及免疫器官胸腺和脾脏指数,明确POA对溃疡性结肠炎的抗炎效果;通过16S rRNA测序分析研究结肠内容物中微生物组成与多样性,明确POA对溃疡性结肠炎小鼠肠道菌群的影响。结果表明,与模型组相比,给药组小鼠体质量明显恢复,DAI评分、脾脏指数极显著降低(P<0.01)、胸腺指数极显著升高(P<0.01)。其中SPI-POA组的作用更加明显;POA改善并恢复UC小鼠肠道菌群的菌种丰度,促进有益菌Muribaculaceae和Lactobacillus的增殖,缓解炎症导致的菌种比例失调,且POA组和SPI-POA组的作用趋近于PC组。因此,SPI-POA可以通过调节肠道菌群多样性及菌群结构来改善UC,是一种潜在的植物源抗炎食品。

硫酸钠废盐资源化处置研究

基于硫酸钠与碳酸氢铵联合制碱的原理,研究了硫酸钠初始质量浓度、反应时长、反应物物质的量比等因素对产物碳酸钠质量分数和原料硫酸钠转化率的影响;对制碱得到的母液,以蒸发浓缩进行分盐处理,考察了硫酸、浓缩倍数和冷却温度等因素对所得盐中硫酸铵质量分数的影响。硫酸钠制碱实验的最优条件为:反应时间为1 h,硫酸钠溶液初始质量浓度约为330 g/L,硫酸钠和碳酸氢铵的物质的量比约为1∶1。该条件下,得到的固体碳酸钠质量分数高于90%。经母液蒸发浓缩后,硫酸铵和硫酸钠以复盐的形式析出,硫酸铵质量分数可达到85%。加入硫酸、提高浓缩倍数、降低冷却温度都会降低复盐中硫酸铵的质量分数。

氯碱生产中的节能降耗、清洁生产工艺

介绍了甘肃北方三泰化工有限公司氯碱生产中采取的节能降耗及环保技术/设备。这些技术/设备包括:一拖二整流变压器;膜法除硝及元明粉的生产;无机膜盐水精制技术;膜极距电解槽;废气和废水的在线监测仪。

Bilayer characteristics and cholesterol effects of sodium dialkylmethyl sulphates

The gel-liquid crystal phase transitions(PT)in bilayers formed from a series of synthetic sodium dialkylmethyl sulphates have been studied by both fluorescence and differential scanning cal- orimetry(DSC)methods,which are between the transitions of the corresponding phospholipids and the quarternary ammonium salt bilayers possessing the same hydrocarbon chains.The fluorescence I_3/I_1 ratio(R)of probe pyrene in the bilayers decreases below and increases above the transitions respectively with increasing the chain length of the surfactants in the series SUDS,SPHS,and SHOS.In addition, the difference between the R above and below the transition(⊿R)is larger in the suspension prepared at the temperature above that of the transition than in that formed at room temperature.Intermem- brahe transfer and transbilayer migration(flip-flop)evaluated by means of DSC of a mixture of equi- molar aqueous dispersions of SHOS and SPHS as well as by ESR of bilayer embedding the stable free radical 4-HD-TEMPO in the presence and absence of excess ascorbic acid take place noticeably only at the temperature above that of the transitions.Cholesterol has shown the same effect on ⊿R as to decrease the length of the alkyl chain of the surfactants.It also causes a decrease of the fluorescence Intensity ratio of excimer to monomer of pyrene,I_e/I_m(S),in both phase.The results are discussed in terms of bilayer structure,chain fluidity,and permeability of water.

十二烷基甜菜碱/十二烷基硫酸钠复配体系的表面活性

研究了两性表面活性剂十二烷基甜菜碱（Ｃ１２ＢＥ）和阴离子型表面活性剂十二烷基硫酸钠（ＳＤＳ）复配体系的形成胶束能力．降低表面张力效率，降低表面张力能力三种增效作用 发现Ｃ１２ＢＥ和ＳＤＳ摩尔比为６：４时增效作用最显著．并考察了盐、醇对复配体系表面活性的影响，结果表明，加盐能导致表面活性的提高．加醇的机理比较复杂，乙醇对复配体系表面活性影响不大，而正丁醇影响则比较显著．

在硫酸钠熔盐中合成莫来石晶须

采用Al2(SO4)3·18H2O和SiO2作为反应原料,在Na2SO4熔盐中合成了莫来石晶须,利用XRD、FESEM和SEM等手段研究了合成产物的组成和形貌,并研究了合成温度(700℃、800℃、900℃、950℃、1000℃、1100℃和1200℃)、熔盐用量(反应料与Na2SO4的质量比分别为2:1、1:1、1:2和1:4)、保温时间(2h、3h和4h)等工艺因素对合成反应的影响。结果表明:用熔盐法合成的莫来石不含其他晶相,纯度高,晶须直径在50～150nm,长度为3～8μm。研究还发现:Na2SO4熔盐的合适用量为反应料与Na2SO4的质量比是1:1,此时,混合料在900℃开始生成莫来石,950℃石英相基本消失,1000℃保温3h合成反应基本完成,超过1100℃时,合成的莫来石开始分解。因此,熔盐法合成莫来石的合理温度为1000℃保温3h。